JPH0683864B2 - High rigidity core manufacturing method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for producing a highly rigid core, and more particularly to a new method for producing a superplastically formed core that enables the production of a highly rigid and high performance core. It is a thing.

(Prior Art) Lightweight and highly rigid panels for satellite structures and equipment installations have been required, and bonded honeycombs have been used as the cores of panels for the past. In a panel that is required to have characteristics, it is necessary to metallically bond the core and the phase plate, and it has been attempted to use a superplastic molded body as the core.

A conventional superplastic forming core is manufactured by forming a superplastic metal plate by a gas pressure or a fluid pressure in either one of a male type and a female type in which a core shape is carved.
Superplastic forming cores according to the conventional method are roughly classified into two types of shapes as shown in FIGS. 3 (a) and 3 (b).
That is, the corrugated shape in FIG. 3 (a) and the crossed corrugated shape in FIG. 3 (b). Regarding the cross corrugated shape, there are a case where the corrugated portion is formed and a case where the opposite portion is formed.

(Problems to be Solved by the Invention) This conventional superplastic forming method and superplastic forming core have the following drawbacks.

(1) The mold used for molding must have the core shape as it is, and it is expensive to manufacture the mold, and it is difficult to manufacture a mold for molding a complicated shape such as a continuous double curved surface.

(2) Since the superplastic metal plate is stretched and formed in one direction from the concave portion of the die, the thickness of the filter plate is remarkably reduced at the forming portion, and the plate thicknesses of the upper surface and the lower surface of the superplastic forming core are significantly different.

(3) In the corrugated core, the reinforcement of the panel is limited to one direction. Moreover, since the cross-corrugated core does not have rigidity by itself, a separate component is required to give rigidity to the intersection.

In view of the above-mentioned drawbacks, the present inventors have a strengthening direction of two or more directions without joining step (in a single core) when manufacturing a superplastic forming core, and do not generate a plate thickness distribution on the upper and lower surfaces of the core. The present invention was devised during the course of various studies on the shape and molding method of such a high-rigidity core.

(Means for Solving the Problems) The present invention relates to an upper die and a lower die having columnar protrusions arranged alternately and regularly, and pressing a metal plate in a superplastic state by sandwiching the metal plate. In the method of manufacturing a high-rigidity core in which both surfaces of the upper mold are stretched, the distance between the protrusions of the upper mold and the lower mold at the meshing position is larger than the thickness of the metal plate. Using a mold, the metal plate is bulged, and formed on the front and back sides of the metal plate, corresponding to the projections, and between the tip and the tip without contacting the side surface of the projections. A method of manufacturing a high-rigidity core, which comprises manufacturing a core having an inclined portion.

A specific example of the method of the present invention is shown in FIGS.

In the method of the present invention, an upper mold and a lower mold are used, and as shown in FIG. 1 (a), the upper mold protrusion 2 represented by a white circle ○ and the lower mold protrusion 3 represented by a black circle are: They are provided at positions which are arranged alternately and regularly with respect to one plane of the test material having superplasticity. Then, at the position where the upper die and the lower die are engaged with each other, the gap between the columnar protrusions of the upper die and the lower die is made wider than the plate thickness of the metal plate which is the object to be molded, so that the columnar protrusions of the upper die and the lower die columnar The metal plate located between the protrusions is deformed without contacting the side surface of the columnar protrusion to form the inclined portion of the core. Hereinafter, A- in FIG.
This will be described with reference to FIGS. 1 (b) to (d) showing the A'section.

The test material 1 having superplasticity is set between the upper die 4 and the lower die 5 having the protrusions 2 and 3 arranged alternately and regularly, and the periphery is restrained by the holding jig 6. ing. The upper die is directly connected to the press drive shaft 7, and is driven gently while keeping parallel with the lower die.
A heater 8 for heating is arranged around these processing jigs [FIG. 1 (b)]. The test material 1 is heated by the heater 8 to a temperature at which it exhibits superplasticity, and then the upper die 4 is driven so as to sandwich the test material 1 so that the test material 1 is alternately stretched in both front and back directions. A high-rigidity core having front and back surfaces of the plate corresponding to the columnar protrusions of the upper mold and the lower mold and an inclined portion formed between the tip and the tip without contacting a side surface of the columnar protrusion is provided. It is manufactured [Fig. 1 (c) and (d)].

In the above example, the test material restraining jig 6 is for completely stretch-molding up to the peripheral portion, and is not particularly necessary when trimming the periphery of the molded product for use. Further, the die driving system may use either gas pressure or fluid pressure driving, or mechanical driving such as gears in addition to the above press driving, and the driving die is only the upper die, only the lower die, In either case of the two molds, the relative position of the mold with respect to the test material does not change, so it does not matter which mold is driven. The heater may be placed on the upper and lower surfaces instead of the side surface of the mold, and the jig structure may be placed horizontally. The characteristics of the superplastic forming core can be controlled by changing the length and spacing of the protrusions or the shape and arrangement of the protrusions. For example, in the example of FIG. 1 (a), the projections are arranged so as to strengthen in two directions, but when arranged as shown in FIG. 2, strengthening in three directions is possible. In FIG. 2, a white circle ◯ indicates the position of the upper die protrusion, and a black circle ● indicates the lower die position.

(Effect of the Invention) The method of the present invention has the following features.

Since the mold has only regularly arranged protrusions, it is cheaper than the conventional superplastic forming mold.

Since the superplastic metal plate is formed by bulging in both front and back directions by the protrusions of the upper and lower molds, the thickness of the molded core is the same on the upper and lower surfaces, and the uneven thickness of conventional superplastic molded cores does not occur. Absent.

The core manufactured by the method of the present invention has a high rigidity by itself, and the reinforcing direction can be set to two or three directions depending on the arrangement of the protrusions.

Therefore, the method of the present invention can be applied as a molding method for cores or panel bodies of all panel structures that require light weight, high strength, and high rigidity. According to the present invention, the obtained core is a core formed from a single plate, and since the joint portion with the face plate is a surface, metal joining is easy, so that characteristics such as high heat conduction and high electric conduction are required. It is applicable as a manufacturing method of the core of the panel.

[Brief description of drawings]

FIGS. 1 (a) to 1 (d) are views for explaining an embodiment of the present invention, and FIG. 1 (a) is a view showing the positional relationship between upper and lower mold projections, and FIG. ) To (d) are A in FIG.
Taking the part corresponding to the -A 'cross-section as an example, Fig. 7 (b) shows the test material in the set state, Fig. 6 (c) shows the state in the middle of pressing, and Fig. 6 (d).
[Fig. 6] is a view showing a pressed state. FIG. 2 is a view showing a positional relationship between upper and lower projections in another embodiment of the present invention. 3 (a) and 3 (b) are views illustrating a conventional superplastic forming core, in which FIG. 3 (a) shows a corrugated shape and FIG. 3 (b) shows a crossed corrugated shape.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shoichiro Asada 10 Oe-machi, Minato-ku, Nagoya, Aichi Mitsubishi Heavy Industries, Ltd., Nagoya Aircraft Manufacturing Co., Ltd. (56) Reference JP-A-46-7095 (JP, A)

Claims (1)

[Claims] 1. A high die for forming a metal sheet in a superplastic state by sandwiching a metal sheet in a superplastic state with an upper die and a lower die having columnar protrusions arranged alternately and regularly to form a bulge on both sides of the metal sheet. In the method of manufacturing a rigid core, the metal plate is formed by using an upper mold and a lower mold in which the distance between the protrusions of the upper mold and the lower mold at the meshing position is larger than the thickness of the metal plate. Protrusion molding is performed to manufacture a core having front and back surfaces of the metal plate, which have tip portions corresponding to the protrusions, and inclined portions formed between the tip portions and the tip portions without contacting side surfaces of the protrusions. A method for manufacturing a high-rigidity core, which is characterized in that